Английская Википедия:Ciomadul

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Шаблон:Short description Шаблон:Good article Шаблон:Infobox mountain Ciomadul (Шаблон:Lang-hu) is a dormant volcano in Romania.Шаблон:Sfn It is in the Eastern Carpathians, between the spa towns of Băile Tușnad and Balvanyos. Ciomadul lies at the southeastern end of the Carpathian volcanic chain and it is the youngest volcano of the Carpatho-Pannonian region. Ciomadul consists of several lava domes with two embedded explosion craters known as Mohoș and Sfânta Ana, the latter of which contains a crater lake, Lake Sfânta Ana. The dominant volcanic rock at Ciomadul is potassium-rich dacite.

Volcanic activity at Ciomadul commenced with effusive activity about one million years ago. Most of the volcano was constructed between 650,000 – 500,000 years ago.

Between 56,000 and 32,000 years ago explosive volcanic activity occurred at Ciomadul. Both the exact dates of the various eruptions and of the formation of the Sfânta Ana and Mohoș craters are unclear, partly because dates obtained by potassium-argon dating and other dating techniques deviate from each other. Some eruptions may have reached sub-Plinian strength, ejecting volcanic ash as far as the Black Sea.

The last eruption took place between 32,600 and 27,500 years ago. Its date is likewise unclear. Ongoing seismic and geothermal activity, and exhalations of volcanic gas and evidence of a still existing magma chamber indicate that Ciomadul is a potentially active volcano.

Geography and geology

Regional setting

With the exception of Greece and Italy, the most recent volcanic activity in Continental Europe occurred between 40,000 and 6,500 years ago in Garrotxa, the Massif Central and the Vulkaneifel.Шаблон:Sfn

Volcanism in the region of Carpathia and Pannonia has been ongoing since 20 million years ago but has decreased during the Quaternary. No eruptions took place in the Holocene.Шаблон:Sfn The last volcanism occurred at Ciomadul in the last glacial age.Шаблон:Sfn Sparse basaltic volcanism has also taken place in the area, forming monogenetic volcanic fields.Шаблон:Sfn

A Шаблон:Convert volcanic arc lies in the Carpathians. In its southern segment, also known as the Călimani (Kelemen) – Gurghiu (Görgényi) – Harghita (Hargita) chain,Шаблон:SfnШаблон:SfnШаблон:Sfn volcanism has migrated between 9 and 0.22 million years ago southward, forming a Шаблон:Circa Шаблон:Convert volcanic chain.Шаблон:Sfn Magma output progressively decreased during time, with early volcanoes being large stratovolcanoes sometimes featuring caldera-forming eruptions, while more recent activity includes monogenetic volcanoesШаблон:SfnШаблон:Sfn although more precise dating and volume estimation efforts at Ciomad have found an increase of eruption rates over time.Шаблон:Sfn

This volcanism occurs in a setting where the collision between the Eurasian Plate and the Tisza-Dacia microplate took place,Шаблон:SfnШаблон:Sfn preceded by a stage of subduction involving a narrow ocean.Шаблон:Sfn This is part of the collision between the African Plate and the Eurasian Plate; subduction may still be underway in the area of the Carpathians.Шаблон:Sfn The Шаблон:Ill, which is Шаблон:Convert away from Ciomadul, features ongoing earthquake activity; deep earthquakes suggest that a remnant of a slab exists beneath the Vrancea Zone.Шаблон:Sfn This tectonic setting may also be responsible for ongoing exhumation in the southeastern Carpathians,Шаблон:Sfn volcanism at Ciomadul and the Perșani volcanic field,Шаблон:Sfn Шаблон:Convert south of Ciomad,Шаблон:Sfn which was concurrently active to the older Ciomadul activity.Шаблон:Sfn Other theories on Ciomadul's volcanic activity imply delamination of the lithosphere or roll-back of the subduction zone.Шаблон:Sfn

Volcanism in this chain is calc-alkaline, yielding both andesite, dacite,Шаблон:Sfn and rhyolite.Шаблон:Sfn Three million years ago, a change in the chemistry of volcanism occurred, with an increased content of potassium in the rocks. This change in composition geographically coincided with the volcanic activity crossing a lineament known as the Trotuș line.Шаблон:SfnШаблон:SfnШаблон:Sfn

Volcano

Файл:Lacul Sfanta Ana - Panoramic.gif
3D model of the volcano

Ciomadul is located in the southeastern Carpathians,Шаблон:Sfn at the end of the Călimani (Kelemen) – Gurghiu (Görgényi) – Harghita (Hargita) volcanic chain,Шаблон:Sfn and is also known as Csomád in Hungarian.Шаблон:Sfn The gorge of the Olt River separates Ciomadul from the Harghita Mountains.Шаблон:Sfn The towns of Băile Tușnad and Bixad are close to the volcano,Шаблон:Sfn and a road leads up the volcano from the southeast and goes past the Mohoș swamp to Lake Sfânta Ana.Шаблон:SfnШаблон:Sfn The basement of the volcano is formed by flysch of Cretaceous ageШаблон:SfnШаблон:Sfn and by older volcanics; in some places volcanic rocks overlie fluvial deposits.Шаблон:Sfn

Places around Ciomadul were first mentioned in 1349;Шаблон:Sfn the Saxon mineralogist Johann Ehrenwert Fichtel was the first to interpret it as a volcano, in 1780.Шаблон:Sfn The idea that Ciomadul could be a still active volcano was first proposed in the same year on the basis of its young appearance and the release of gas.Шаблон:Sfn These discoveries drew scholars and visitors to the volcanoШаблон:Sfn and the first scientific analysis of the volcano was published just eight years later.Шаблон:Sfn While a publication in 1964 postulated that the tuffs of Ciomadul were reworked Pliocene volcanites, the late Pleistocene age was established soon afterwards.Шаблон:Sfn The volcano is the youngest volcanic centre in the CarpathiansШаблон:Sfn and has a more rugged appearance than the surrounding mountains.Шаблон:Sfn

Ciomadul is formed by a complex of lava domes and other volcanic material that form a south-tilting ridge that rises above the Шаблон:Convert surrounding Lower Ciuk Basin. Individual lava domes form cone-shaped hills,Шаблон:Sfn which reach heights of Шаблон:Convert and widths of Шаблон:Convert. Individual domes include Haramul Ierbos (Fű-Haram in Hungarian), Haramul Mare (Nagy-Haram), Haramul Mic (Kis-Haram), Vf. Cetății (Vár-tető), Vf. Comloș (Komlós-tető), Vf. Surduc (Szurdok-tető)Шаблон:Sfn and Dealul Mare southeast from the main complex.Шаблон:Sfn The central cluster of domes is ellipticalШаблон:Sfn and tectonic faults influenced their growth.Шаблон:Sfn The highest point of the complex is Ciomadul Mare (Nagy-Csomád) with an altitude of Шаблон:Convert.Шаблон:Sfn Some domes were later affected by erosion, explosive activityШаблон:Sfn or fumarolic alteration.Шаблон:Sfn The whole volcanic complex covers a surface area of Шаблон:Convert,Шаблон:Sfn and is surrounded by a circular/semicircular plain made of volcanic debris.Шаблон:Sfn

Файл:Szent Anna tó 3.jpg
Sfânta Ana crater and lake

The lava dome complex contains two craters, named Mohoș and Sfânta Ana. They were formed in the previously existing lava domesШаблон:SfnШаблон:Sfn which form the western margin of the craters, while products of explosive eruptions crop out in the east.Шаблон:Sfn The Sfânta Ana crater is Шаблон:Circa Шаблон:Convert wide and Шаблон:Circa Шаблон:Convert deep beneath the rim, comparable with the crater of El Chichón volcano in Mexico.Шаблон:Sfn This crater lacks a breach and is relatively unaffected by erosion.Шаблон:Sfn It contains a Шаблон:Convert crater lake,Шаблон:Sfn which once may have been over Шаблон:Convert deep. This Шаблон:Circa Шаблон:Convert lake is known as Lake Sfânta Ana (Шаблон:Coord) and lies at an altitude of Шаблон:Convert;Шаблон:SfnШаблон:Sfn its ecosystem and environment has drawn the attention of scientists for two centuries.Шаблон:Sfn

The Mohoș crater lies at an altitude of Шаблон:Convert.Шаблон:Sfn It is larger than Sfânta Ana with a diameter of Шаблон:Convert and not as deepШаблон:Sfn with its bottom lying above sea level. It is filled with a Шаблон:Convert and Шаблон:Convert Sphagnum peat bog and its rim is cut by the Sfânta Ana crater.Шаблон:SfnШаблон:Sfn

Файл:Mohos Peat Bog 1.jpg
Peat bog in Mohoș crater

Unlike Sfânta Ana, the Mohoș crater has been breached by erosion, causing the formation of an outlet valley.Шаблон:Sfn Both craters were formed by explosive eruptions and distinguishing between the deposits of both is difficult.Шаблон:Sfn The existence of an even larger crater with a diameter of Шаблон:Convert has been suggested,Шаблон:Sfn encompassing both Sfânta Ana and Mohoș.Шаблон:Sfn

Pyroclastic flow deposits generated by Ciomadul have been found on its northeastern, southern and western slopes.Шаблон:Sfn They reach a distance of as much as Шаблон:Convert from the volcano.Шаблон:Sfn At Tușnad road, one of the flows has a thickness of Шаблон:Circa Шаблон:Convert.Шаблон:Sfn Tephra fall bed,Шаблон:Sfn lapilli,Шаблон:Sfn and surge deposits are also found, and the flow deposits contain pumice blocks.Шаблон:Sfn One lapilli layer, Шаблон:Convert thick, from Ciomadul has been identified Шаблон:Convert east of the volcano.Шаблон:Sfn The whole pyroclastic formation has been subdivided into three classes known as "Early Phreatomagmatic + Plinian Activity", "Middle Plinian Activity" and "Latest Sfânta Ana Phreatomagmatic Activity". Each comprise a number of individual tephra layersШаблон:Sfn that were erupted 42,000—40,000, around 31,500 and 29,000—28,000 years ago.Шаблон:Sfn Some of these eruptions may have dammed the Olt river; when the river returned on its course it produced lahar deposits.Шаблон:Sfn

Other landforms at Ciomadul include coulees and lava flows.Шаблон:Sfn The total volume of the complex is about Шаблон:Convert dense rock equivalent.Шаблон:Sfn Drilling has identified the existence of an intrusion at a depth of Шаблон:Convert.Шаблон:Sfn Finally, volcanic erosion products and tephra occur all over the volcanic complexШаблон:Sfn and up to Шаблон:Convert east of it.Шаблон:Sfn

Older volcanic centres extend northwest of Ciomadul. With increasing distance they are the 2.5—1.5 million-year-old Pilisca centre, the 2.8—2.2 million-year-old Cucu centre and the 4.3—3.6 million-year-old Luci-Lazu and Șumuleu-Ciuc volcanic centres. South of Ciomadul the Murgul shoshonites were erupted 2.3—1.5 million years ago;Шаблон:SfnШаблон:Sfn they represent cryptodomes.Шаблон:Sfn Andesite lava flows from Pilisca underlie the Ciomadul deposits in some places.Шаблон:Sfn

Composition

The principal rock is dacite, which defines a potassium-rich calc-alkaline suite.Шаблон:Sfn The rocks have a porphyric appearance and contain few vesicles. They are also very rich in crystals,Шаблон:SfnШаблон:SfnШаблон:Sfn with the dominant phenocryst-forming minerals being biotite, hornblende and plagioclase. Less important are allanite, apatite, clinopyroxene, olivine, orthopyroxene, quartz, sphene and zircon.Шаблон:SfnШаблон:Sfn The groundmass contains plagioclase, pyroxene, silicon dioxide and oxides of iron and titanium.Шаблон:Sfn Clots formed by various felsic crystals are common.Шаблон:Sfn The composition of Ciomadul's rocks has been fairly constant throughout its evolutionШаблон:Sfn albeit with two shifts 1 million and 650,000 years before present,Шаблон:Sfn and this diversity of its components indicate that the genesis of Ciomadul magmas involved mixing between felsic and mafic magma.Шаблон:Sfn The phenocryst compositions at Ciomadul are unlike these at other volcanoes in the Carpathians.Шаблон:Sfn The magmas derive from the upper mantle lithosphere, which underwent metasomatic alteration.Шаблон:Sfn

Compositionally, the tephras of Ciomadul have been subdivided into two groups, one called Tușnad‐type and the other Bixad‐type.Шаблон:Sfn A large proportion of crystals in the rocks consists of antecrysts and xenocrysts, making radiometric dating of the rocks difficult. These include amphibole, biotite, feldspar and zircon.Шаблон:Sfn The zircons formed almost continuously over hundred thousands of years within Ciomadul's magma chamber, indicating a steady crystallization of the chamber.Шаблон:Sfn Differences in magma temperature, crystal content and the participation of pre-existent crystal mushes determine whether an eruption will be effusive or explosive.Шаблон:Sfn

The temperature of the magma chamber has been estimated to be about Шаблон:Convert, with heating of over Шаблон:Convert occurring before some eruptions according to thermometry calculation. Volcanic activity was most likely triggered by the injection of basaltic magma into the felsic magma chamber before the actual eruption,Шаблон:SfnШаблон:Sfn as has been observed at other silicic volcanoes around the world,Шаблон:Sfn but the magma chamber probably kept being recharged even between eruptions.Шаблон:Sfn The amphiboles in the rocks formed at depths of Шаблон:Convert.Шаблон:Sfn The magma output of Ciomadul is about Шаблон:ConvertШаблон:Sfn while magma chamber recharge may have reached Шаблон:Convert.Шаблон:Sfn

Eruptive history

Ciomadul has been active for over half a million years,Шаблон:Sfn with the oldest activity between 1,000,000 and 750,000 years ago forming lava domes.Шаблон:SfnШаблон:Sfn Older estimates indicate that activity did not start before 250,000 years ago, while more recent research indicated a start of volcanism over 600,000/Шаблон:SfnШаблон:Sfn 850,000 years ago.Шаблон:Sfn Volcanism at Ciomadul consisted mostly of the extrusion of lava domes, their collapse forming block-and-ash flows and subplinian and Vulcanian eruptionsШаблон:Sfn separated by long periods of rest.Шаблон:Sfn The volcanic history of Ciomadul has been subdivided into an effusive phase that lasted until about 440,000 years ago and an explosive phase that began 200,000 years agoШаблон:Sfn during which magma output increased 30-foldШаблон:Sfn and which is known as "young Ciomad".Шаблон:Sfn An alternative description envisages an "old Ciomadul" between 1,000,000 — 300,000 years ago and a "young Ciomad eruptive period" between 160,000 — 30,000 years ago, with the latter in turn subdivided into five stages that emplaced about Шаблон:Convert of rock.Шаблон:SfnШаблон:Sfn

A gap of about 500,000 years separates Ciomadul from the activity of other volcanoes in the area.Шаблон:Sfn The two oldest dates of 1,020,000 and 850,000 years ago were obtained on peripheral lava domes.Шаблон:Sfn Early activity between Шаблон:Circa 850,000 — 440,000 years ago built the southeastern domes.Шаблон:Sfn This effusive phase is also known as "old Ciomad",Шаблон:Sfn and eruptions were separated by long pauses without volcanic activity from each other.Шаблон:Sfn The dates obtained by potassium-argon dating are much older;Шаблон:Sfn there is substantial disagreement between dates obtained by potassium-argon dating or argon-argon dating on the one hand and uranium-thorium dating on the other hand at Ciomadul.Шаблон:SfnШаблон:Sfn These dates indicate that the formation of the central lava domes took place between 590,000 and 140,000 years ago.Шаблон:Sfn

Around 200,000 — 130,000Шаблон:Sfn or 150,000 — 100,000 years ago a number of lava domes developed.Шаблон:Sfn Explosive eruptions became common only about 57,000 years ago.Шаблон:Sfn Between 56,000 and 32,000 years ago, explosive activity occurred at Ciomadul. That timespan coincides with the deposition of tephra from volcanoes in Italy in Europe; it is possible that tephra also came from Ciomadul.Шаблон:Sfn Indeed, the age of Ciomadul's last eruption overlaps with the age of the Campanian Ignimbrite.Шаблон:Sfn

Tephras

Ciomad has produced far-flung tephras, which reached as far as UkraineШаблон:Sfn and have been recovered from the Ursului Cave of the Perșani Mountains.[1] Some tephra layers found in two drilling cores of the Black Sea may have originated at Ciomad[2] but reliably distinguishing between Ciomadul tephras and these from Nisyros and Anatolian volcanoes is difficult.Шаблон:Sfn

The Roxolany Tephra has been found as far as Odesa, Ukraine, Шаблон:Convert away from Ciomadul.[3] If the Roxolany Tephra was formed by the youngest eruption of Ciomadul, the youngest eruption would have occurred 29,600 calibrated radiocarbon years ago based on independent dates of the tephra.[2] From the other point of view, the clinopyroxene‐bearing Roxolany tephra was unlikely to be derived from Ciomadul, as it differs significantly from Ciomadul typical phenocryst assemblage containing amphibole.Шаблон:Sfn Based on new chronostratigraphic model for the Roxolany section, supported by updated magnetostratigraphic results and compiled existing radiocarbon and optically stimulated luminescence dates, the Roxolany tephra was deposited around 143,800 years ago.[4]

Recent explosive activity

Explosive activity may have occurred in two separate episodes, one 57,000/56,000–44,000 years ago and the other 34,000/33,000–29,000 years ago.Шаблон:SfnШаблон:Sfn An earlier explosive eruption about 55,900 ± 2,300 years ago may be the origin of the Mohoș crater,Шаблон:Sfn with another proposed potassium-argon date being Шаблон:Circa 220,000 years ago. Mohoș crater is probably older than the Sfânta Ana crater.Шаблон:Sfn A phreatomagmatic deposit northeast of Mohoș was formed by an eruption of the Mohoș crater;Шаблон:Sfn this eruption may be the source of the "Turia type" phreatomagmatic deposits,[3] which are dated to have occurred about 51,000 ± 4,800 years ago.Шаблон:Sfn In one view, a volcanically quiet period followed an effusive eruption 48,000Шаблон:Sfn or 42,900 years ago named "Piscul Pietros" and lasted until 31,510 years ago,Шаблон:Sfn when a Plinian eruption occurred. This latter eruption deposited Шаблон:Convert ash as far as Шаблон:Convert from the vent at one site.Шаблон:Sfn Alternatively, 38,900 ± 1,700 years ago a subplinian eruption occurred at Ciomadul; it may have formed the Sfânta Ana crater.Шаблон:Sfn This date would correspond to that of the so-called "MK-202" tephra.[5] Piscul Pietros has been also dated to be 48,000 ± 6,000Шаблон:Sfn or 60,000 ± 5,000 years old.Шаблон:Sfn

The age of the last eruption is controversialШаблон:Sfn but probably took place about 30,000 years ago.Шаблон:Sfn In 1994, radiocarbon dating yielded an age of 10,700 ± 800 years Before Present from a pyroclastic flow. Later, paleosoils and other samples from the same flow were used to deduce similar ages of over 36,770, 42,650, over 35,670 and over 35,520 years before present, respectively.Шаблон:Sfn Thus this youngest age estimate was discarded.Шаблон:Sfn In 2010, further research identified two younger eruptions, one occurring 39,000 years Before Present and the other 27,500 years Before Present.Шаблон:Sfn Other data obtained by uranium-thorium dating indicate an age of 32,600 ± 1,000 years ago for the youngest eruption.Шаблон:Sfn Both of these eruptions took place at Sfânta Ana and imply a repose period between eruptions of over 10,000 years.Шаблон:Sfn Much older dates obtained by potassium-argon dating are not considered reliable.Шаблон:Sfn Alternatively, the latest eruption may have occurred at a satellite vent seeing as sedimentation of Lake Sfânta Ana has been ongoing since 26,000 years ago.Шаблон:Sfn These two recent eruptions were fed by different magmas, with the younger eruption coming from deeper magma chambers (Шаблон:Convert versus Шаблон:Convert) and involving more primitive magma.Шаблон:Sfn

After the last eruption, the lava domes were subject to glacial weathering, such as frost shattering that produced stone runs.Шаблон:Sfn An 1838 document by an unknown author stated that even old legends do not record eruptive activity at Ciomadul,Шаблон:Sfn and there is no evidence in Lake Sfânta Ana sediments of tephra layers that might indicate more recent eruptions.Шаблон:Sfn

Current status

Presently, Ciomadul displays seismic activity,Шаблон:Sfn release of carbon dioxide from bubbling pools and bogs and mofettasШаблон:Sfn and anomalous heat flowШаблон:Sfn reaching Шаблон:Convert.Шаблон:Sfn Outgassing of carbon dioxide, hydrogen sulfide and mostly abiotic methane have been found at Ciomadul,[6] forming sulfide deposits in some caverns.Шаблон:Sfn The total output of carbon dioxide exceeds about Шаблон:ConvertШаблон:Sfn per year, while the output of methane amounts to Шаблон:Convert per year.[6] Carbon dioxide concentrations in some places such as caverns can be high enough to become dangerous to people and animals, and is reflected in place names - such as Peștera Ucigașă (Gyilkos-barlang) which mean "killer cave"Шаблон:Sfn while Puturosu means "stinky" - Шаблон:Sfn and local legends of a "gate to hell".Шаблон:Sfn Former alum and sulfur mines east of Ciomadul were abandoned due to the dangers from toxic gases.Шаблон:Sfn The carbon dioxide is accompanied by noble gases derived from the mantle.Шаблон:Sfn The gases may come directly from the mantle, rather than from magma.Шаблон:Sfn

At depths of Шаблон:Convert and especially Шаблон:Convert,Шаблон:Sfn a magma chamber has been identified beneath Ciomadul,Шаблон:SfnШаблон:Sfn based on magnetotelluric data,Шаблон:Sfn and several Шаблон:Convert of magma may still be stored underneath Ciomadul.[7] An alternative explanation is that there are less than a few cubic kilometres of magma.Шаблон:Sfn This magmatic reservoir appears to have about 5—15% of melt by volume fraction,Шаблон:Sfn with a vertical stratification by temperature.Шаблон:Sfn A deeper basaltic melt zone may also exist[8] at a depth of around Шаблон:Convert.Шаблон:Sfn Further, a zone of low seismic velocity has been identified with geophysical and seismic modelling in the lower crust and upper mantle beneath Ciomad, down to depths of Шаблон:Convert or Шаблон:Convert.Шаблон:Sfn

Hydrothermal activity has been noted at Ciomadul and Tușnad-Băi, including a high temperature system at depth with temperatures exceeding Шаблон:Convert.Шаблон:Sfn The Tușnad-Băi springs have temperatures of Шаблон:Convert and discharge salty, carbon dioxide-rich water which emerges from pyroclastic deposits.Шаблон:Sfn They are used in spas in the area.Шаблон:Sfn In one cave, autotropic bacterial biofilms have been found which subsist on the exhaled gases or the sulfur deposits.Шаблон:Sfn

Future activity

Volcanoes are usually considered to be active if they have had eruptions during the Holocene. However, as demonstrated by the unexpected eruption of Chaiten volcano in Chile in May 2008, even long-inactive volcanoes can become active again. Such volcanoes can constitute a threat to regions with seemingly quiet volcanism.Шаблон:Sfn Ciomadul has had repose periods that lasted longer than the timespan elapsed since the last eruption.Шаблон:Sfn Zircon crystallization data imply that the magma chambers of Ciomadul were active over time spans of over 300,000 years.Шаблон:Sfn

Uniquely, Ciomadul is a still alive volcano in Eastern Europe and its craters have a youthful appearance.Шаблон:Sfn There is always the possibility of renewed volcanic activity if the magma chamber has not solidifiedШаблон:Sfn even if there is no positive evidence of ongoing magma generation.Шаблон:Sfn Deep earthquake activity at Ciomadul occurs down to a depth of Шаблон:Convert, indicating that the volcanic system between the magma chamber and lithospheric melts is still active.Шаблон:Sfn It is considered to be a potentially active volcanoШаблон:Sfn although the risk of impending eruptions has been greatly exaggerated by sensationalist media.Шаблон:Sfn Potential eruptions may be heralded by seismic swarms caused by the ascent of magma, followed by deformation of the edifice and degassing in the last weeks and hours before the eruption.Шаблон:Sfn

Climate and vegetation

Ciomadul is located in a temperate climate zone. Rainfall reaches Шаблон:Convert, resulting in strong erosion.Шаблон:Sfn The annual mean temperature is Шаблон:Convert at Sfântu Gheorghe, the nearest meteorological station.Шаблон:Sfn Around Sfânta Ana, July mean temperatures are Шаблон:Convert and January temperatures are Шаблон:Convert.Шаблон:Sfn

While some glaciation occurred in the Carpathians during the ice ages, no glacial activity is recorded at Ciomadul. The volcano was unforested at that time,Шаблон:Sfn with steppe and tundra vegetation comprising most of the reported flora.Шаблон:Sfn Drill cores from the Mohoș peat bog have been used to reconstruct the past climate and hydrology of the area.Шаблон:Sfn

Ciomadul is covered by beech and spruce forests.Шаблон:Sfn Around Lake Sfânta Ana, the vegetation consists mostly of Fagus sylvatica (common beech) and Picea abies (Norway spruce) woods. Other trees include Acer platanoides (Norway maple), Betula pendula (silver birch), Carpinus betulus (common hornbeam), Pinus sylvestris (Scots pine), Salix caprea (goat willow) and Salix cinerea (grey willow). A fen contains Carex lasiocarpa (slender sedge), Carex rostrata (bottle sedge), Lysimachia thyrsiflora (tufted loosestrife) and Sphagnum angustifolium (fine bogmoss).Шаблон:Sfn At Mohoș, vegetation consists of Alnus glutinosa (common alder), Betula pendula and Salix. The peat bog contains trees (Pinus sylvestris and Betula pubescens (downy birch)) and Ericaceae.Шаблон:Sfn The region of the volcano is a Site of Community ImportanceШаблон:Sfn and some endangered plant species have been identified in the Mohoș bog.Шаблон:Sfn

References

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Bibliography

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External links

Шаблон:Commons category

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  6. 6,0 6,1 Ошибка цитирования Неверный тег <ref>; для сносок KisIonescu2016 не указан текст
  7. Ошибка цитирования Неверный тег <ref>; для сносок Laumonier2018 не указан текст
  8. Ошибка цитирования Неверный тег <ref>; для сносок NovákHarangi2012 не указан текст